This invention relates to an instrument for severing and simultaneously cauterizing an appendage (e.g., a tail) of an animal. More particularly, the invention relates to a hand-held instrument having at least one blade for severing the appendage, the blade being heated in order to cauterize the wound and assist in blood coagulation. Instruments of this general type are disclosed in Chapman U.S. Pat. No. 1,083,386; Lagier U.S. Pat. Nos. 1,456,639 and 1,763,894 and Helbling U.S. Pat. No. 3,117,578.